A composition allows you to group a set of cues together on their own sub-timeline. This can then be used from other timelines similar to how you can play a video. A composition makes it easy to re-use or re-arrange show sections or short snippets. It also makes it easier to apply the same effect to a group of media elements – for instance, to move and scale a set of images together.
A composition behaves like other media elements, such as still images and video clips. It lives in the Media window, from where you can drag it onto any timeline to use it. You can use a composition any number of times – you can even play multiple instances of a composition at the same time.
Similar to a video clip, a composition has a duration and may contain motion. However, as a composition is created within WATCHOUT, there’s no rendering time or other delays involved in changing it. A composition can be looped and/or free running, making it easy to create motion of indefinite duration within WATCHOUT.
A Basic Example
For example, assume you want to add a frame to a video clip, and then make the video clip move across the screen while scaling it up at the same time. Although you could do this by applying the motion and the scaling to the video and the frame image individually, it’s often hard to make the two move together in a cohesive way. Instead, you can add both elements to a composition without applying any motion and scaling to the individual elements. Then use the resulting composition from the main timeline, applying the motion and scaling to the composition as a whole.